brake ducting length

HI,

I have a VY SS Sedan and want to get some brake ducting before the track day in dec. I will just be cable tieing it down so dont need the good looking kits etc.

What length do i need to be able to mount ducting from the front bumper to the brakes? I think a few places in Aust sell it in 11-12foot but online (UK from Ebay) have 1 meter sizes.
Also i was thinking of 3" diameter, would that be enough or to small?

Thanks

edit: i am now looking at this http://cgi.ebay.com.au/ws/eBayISAPI....m=330670926497 as it is a hell of a lot cheaper then paying $315 for 11foot of brake hose from Aust. it will be silicone 76mm. but not sure the meters i should purchase

About 1.5 meters max per side. Depends a bit on how you are going to get air into the hose and location of the out pipe.

When you set it up make sure you allow for turning radias or just dont do full lock. I use A/C plastic duct for a 4 inch air intake, run 2 inch duct and a home made alloy brakeadapter that cable ties on the shock.
There is a company that sells compete kits with duct, the mounts etc. Just get a 4 or 5 inch funnell or similar and you are done.

http://www.lapponline.com/index.php?...ex&cPath=89_91